Which sequence of hormone treatment produces receptive behaviors in an ovariectomized female rat?

A) a small dose of progesterone alone
B) a small dose of oxytocin alone
C) oxytocin dose followed thereafter by a progesterone dose
D) a small dose of estradiol alone
E) a small dose of estradiol followed thereafter by a progesterone dose

Answer: E
Rationale: A small dose of estradiol followed thereafter by a progesterone dose produces receptive behaviors in an ovariectomized female.